Hello everyone,
After my "plan" for a new build has become very uncertain due to various factors, I am now planning to extend my existing house and am trying to get a rough overview of the costs involved.
The existing house has a ground floor of approximately 90m² (970 sq ft) of living space and an extension of around 70m² (750 sq ft). My parents live on the ground floor and will remain there (in case anyone thinks of suggesting "just swap"). The older part of the house has a basement. The upper floor of the older building basically contains the same apartment (I live there).
The extension was designed 20 years ago to allow for an easy vertical extension in terms of structural engineering. So, structurally it’s no problem. The roof just needs to be removed, the ring beam at the rear part raised by about 1.5 meters (5 feet), and a suitable intermediate floor installed. No additional support columns or similar are necessary.
The new extension is planned to include a bathroom, kitchen, living/dining room, and a balcony. Possibly a bedroom instead of the kitchen, though that would mean relocating the kitchen to a room in the old building without existing connections—and I would prefer not to have to tear up the entire old building. The new bathroom could be connected to the existing plumbing with a core drilling, which would minimize demolition work.
I asked an acquaintance with architectural "skills" what kind of costs I should expect. He said an extension is basically like a new build, and I should expect roughly €1800 per m² (about $190 per sq ft) of living space. Does that seem realistic?
How would you roughly estimate the costs for the following items (my amateur estimates in parentheses):
Ring beam masonry (€2,000 with own work)
Installing intermediate floor (€20,000)
New masonry work (€10,000 with own work)
Windows (€20,000)
Roof including facade (€30,000)
Sanitary installations including bathroom and underfloor heating (€20,000)
Building services (electricity, network, etc.) (€8,000 with own work)
Flooring, walls, wood ceiling (€15,000 with own work)
Additional costs (€15,000)
Total: €140,000
Does this sound realistic? Or is something way off from actual costs?
After my "plan" for a new build has become very uncertain due to various factors, I am now planning to extend my existing house and am trying to get a rough overview of the costs involved.
The existing house has a ground floor of approximately 90m² (970 sq ft) of living space and an extension of around 70m² (750 sq ft). My parents live on the ground floor and will remain there (in case anyone thinks of suggesting "just swap"). The older part of the house has a basement. The upper floor of the older building basically contains the same apartment (I live there).
The extension was designed 20 years ago to allow for an easy vertical extension in terms of structural engineering. So, structurally it’s no problem. The roof just needs to be removed, the ring beam at the rear part raised by about 1.5 meters (5 feet), and a suitable intermediate floor installed. No additional support columns or similar are necessary.
The new extension is planned to include a bathroom, kitchen, living/dining room, and a balcony. Possibly a bedroom instead of the kitchen, though that would mean relocating the kitchen to a room in the old building without existing connections—and I would prefer not to have to tear up the entire old building. The new bathroom could be connected to the existing plumbing with a core drilling, which would minimize demolition work.
I asked an acquaintance with architectural "skills" what kind of costs I should expect. He said an extension is basically like a new build, and I should expect roughly €1800 per m² (about $190 per sq ft) of living space. Does that seem realistic?
How would you roughly estimate the costs for the following items (my amateur estimates in parentheses):
Ring beam masonry (€2,000 with own work)
Installing intermediate floor (€20,000)
New masonry work (€10,000 with own work)
Windows (€20,000)
Roof including facade (€30,000)
Sanitary installations including bathroom and underfloor heating (€20,000)
Building services (electricity, network, etc.) (€8,000 with own work)
Flooring, walls, wood ceiling (€15,000 with own work)
Additional costs (€15,000)
Total: €140,000
Does this sound realistic? Or is something way off from actual costs?
B
Bauexperte14 Jan 2016 13:34Hello,
No one can reliably answer these questions for you; there are too many unknown factors.
I would first recommend speaking with a structural engineer, regardless of whether an additional storey was considered at the time or not. Unless the structural analysis clearly confirms that it is safe to build upwards. Perhaps the original structural engineer is still practicing? You can also clarify what effects the extension would have on the existing building (e.g., changes to the roof).
Have you checked with your local building authority whether you are even allowed to add another storey (building permit / planning permission)?
Then you will need a carpenter (possibly a demolition contractor) who can dismantle the old roof and reliably tell you whether you can reuse timber or roof tiles, assuming it is his trade. If clay roof tiles were used, this might be a tricky issue since these materials are quite fragile—this is not ideal for dismantling; tradespeople are usually not delicate technicians.
I see a lot of mentions of electricians; for plumbing and electrical work, a licensed professional is required—companies that allow electrical work in the desired form as well. In this context, you can also check whether the existing heating system is designed for the increased living area and/or whether a replacement is necessary.
Regardless of the dismantling costs, I would estimate that adding the additional storey will cost around 115,000 euros (excluding painting and flooring), if you contract all the necessary work. How much of that can be saved in terms of electrical work through your negotiations will become clear.
What do you mean exactly by additional costs?
Best regards, Bauexperte
Xorrhal schrieb:
No one has an opinion on this? Come on, with so much expertise here, someone can surely give a statement, right? And if anything is unclear, I’m happy to answer your questions
No one can reliably answer these questions for you; there are too many unknown factors.
I would first recommend speaking with a structural engineer, regardless of whether an additional storey was considered at the time or not. Unless the structural analysis clearly confirms that it is safe to build upwards. Perhaps the original structural engineer is still practicing? You can also clarify what effects the extension would have on the existing building (e.g., changes to the roof).
Have you checked with your local building authority whether you are even allowed to add another storey (building permit / planning permission)?
Then you will need a carpenter (possibly a demolition contractor) who can dismantle the old roof and reliably tell you whether you can reuse timber or roof tiles, assuming it is his trade. If clay roof tiles were used, this might be a tricky issue since these materials are quite fragile—this is not ideal for dismantling; tradespeople are usually not delicate technicians.
I see a lot of mentions of electricians; for plumbing and electrical work, a licensed professional is required—companies that allow electrical work in the desired form as well. In this context, you can also check whether the existing heating system is designed for the increased living area and/or whether a replacement is necessary.
Regardless of the dismantling costs, I would estimate that adding the additional storey will cost around 115,000 euros (excluding painting and flooring), if you contract all the necessary work. How much of that can be saved in terms of electrical work through your negotiations will become clear.
What do you mean exactly by additional costs?
Best regards, Bauexperte
Hello and thank you very much for your detailed explanation!
The architect who came by said that, according to the building plans, he doesn’t see any structural problems; if necessary, intermediate beams could be installed. Of course, he will consult a structural engineer once the detailed planning begins. But he said he doesn’t see any issues at all – and that was actually the architect’s original brief.
I haven’t spoken to the building authority yet, but the architect also thinks there won’t be any problems. For one, almost everyone on the street already has mostly two-story extensions by now, and we have already added one floor ourselves. The footprint will not be changed. No part of the extension will be higher than any nearby structure; it will be significantly lower than the original building and not taller than the extensions above or below our property. We won’t be blocking anyone’s light or anything like that. Of course, we will obtain the necessary building permits / planning permissions. If an architect, whom I consider knowledgeable, tells me there are no issues, I tend to trust him, especially since no concrete planning is underway yet.
At the moment, I just want to establish a rough financial framework in order to apply for financing from the bank. If I can’t provide a cost estimate to the mortgage advisor, they won’t consider it – at least that has been my experience so far. Also, I still have existing obligations on the current house from the purchase and financing. I want to include those in the new financing (in 2019 I have to refinance a loan, and if possible I want to combine it with the new financing).
For the roof removal, I am simply assuming that I won’t be able to reuse any materials. This is mainly because the tiles used are not suitable for a lower roof pitch than currently allowed. And that will definitely be the case. So I have to expect a completely new roof and am planning with approximately EUR 30,000 (about USD 32,000) including the facade (I hope). My father can probably arrange disposal quite cheaply.
For DIY work, I have thought about the following:
- Removing the roof covering (since the tiles will have to be disposed of anyway)
- Interior finishing such as wallpapering, wooden ceiling, laying floor panels (the entire floor in the house is covered with panels, all installed by ourselves)
- Breaking through walls to the original building and all related work (so the passage will be “finished”)
- Preparatory work for electrical installation (“chasing” walls, installing boxes, laying cables, etc.) so that the electrician only needs to make the connections
- Preparatory work for plumbing installation (drilling, plaster work, etc.)
- Preparatory work for underfloor heating (laying the plastic mats where the underfloor heating pipes will be placed – we also did this ourselves in the rest of the house)
- Painting work
By additional costs I mean expenses for the architect, building permits / planning permissions, things like “floor protection during roof removal,” builder’s liability insurance, notary fees for financing (mortgage registration), and similar items.
EUR 115,000 (about USD 123,000) sounds very low to me. I had estimated (including demolition and so on) EUR 140,000–160,000 (about USD 150,000–171,000) – and that already subtracts the DIY portion.
Do you really think this budget would be sufficient?
The architect who came by said that, according to the building plans, he doesn’t see any structural problems; if necessary, intermediate beams could be installed. Of course, he will consult a structural engineer once the detailed planning begins. But he said he doesn’t see any issues at all – and that was actually the architect’s original brief.
I haven’t spoken to the building authority yet, but the architect also thinks there won’t be any problems. For one, almost everyone on the street already has mostly two-story extensions by now, and we have already added one floor ourselves. The footprint will not be changed. No part of the extension will be higher than any nearby structure; it will be significantly lower than the original building and not taller than the extensions above or below our property. We won’t be blocking anyone’s light or anything like that. Of course, we will obtain the necessary building permits / planning permissions. If an architect, whom I consider knowledgeable, tells me there are no issues, I tend to trust him, especially since no concrete planning is underway yet.
At the moment, I just want to establish a rough financial framework in order to apply for financing from the bank. If I can’t provide a cost estimate to the mortgage advisor, they won’t consider it – at least that has been my experience so far. Also, I still have existing obligations on the current house from the purchase and financing. I want to include those in the new financing (in 2019 I have to refinance a loan, and if possible I want to combine it with the new financing).
For the roof removal, I am simply assuming that I won’t be able to reuse any materials. This is mainly because the tiles used are not suitable for a lower roof pitch than currently allowed. And that will definitely be the case. So I have to expect a completely new roof and am planning with approximately EUR 30,000 (about USD 32,000) including the facade (I hope). My father can probably arrange disposal quite cheaply.
For DIY work, I have thought about the following:
- Removing the roof covering (since the tiles will have to be disposed of anyway)
- Interior finishing such as wallpapering, wooden ceiling, laying floor panels (the entire floor in the house is covered with panels, all installed by ourselves)
- Breaking through walls to the original building and all related work (so the passage will be “finished”)
- Preparatory work for electrical installation (“chasing” walls, installing boxes, laying cables, etc.) so that the electrician only needs to make the connections
- Preparatory work for plumbing installation (drilling, plaster work, etc.)
- Preparatory work for underfloor heating (laying the plastic mats where the underfloor heating pipes will be placed – we also did this ourselves in the rest of the house)
- Painting work
By additional costs I mean expenses for the architect, building permits / planning permissions, things like “floor protection during roof removal,” builder’s liability insurance, notary fees for financing (mortgage registration), and similar items.
EUR 115,000 (about USD 123,000) sounds very low to me. I had estimated (including demolition and so on) EUR 140,000–160,000 (about USD 150,000–171,000) – and that already subtracts the DIY portion.
Do you really think this budget would be sufficient?
B
Bauexperte14 Jan 2016 16:01Xorrhal schrieb:
By additional costs, I mean the architect's fees, fees for permits (building permit / planning permission), costs for things like "protecting the ground during the dismantling of the old roof," builder's insurance, notary fees for financing (mortgage registration), and similar expenses...EUR 15,000 would, in my opinion, already include a buffer for the above, unless the architect charges excessively. So everything should be fine.Xorrhal schrieb:
EUR 115,000 sounds somehow very low to me. I had calculated (ok, including dismantling, etc.) between EUR 140,000-160,000 – and that already excludes the solar power system.
Do you really think that would be enough?Yes. Plus the costs for dismantling and additional building expenses.Regards, Bauexperte
Hire an architect you trust to submit an initial building inquiry (according to §34 of the Building Code) or directly create a preliminary design if a development plan is available, along with a cost estimate or a detailed cost calculation by trade. This way, all your questions will be thoroughly answered, and you can put the crystal ball away.
Similar topics